Induction of apoptosis by directing oncogenic Bcr-Abl into the nucleus

Oncotarget. 2013 Dec;4(12):2249-60. doi: 10.18632/oncotarget.1339.

Abstract

The chimeric Bcr-Abl oncoprotein, which causes chronic myeloid leukemia, mainly localizes in the cytoplasm, and loses its ability to transform cells after moving into the nucleus. Here we report a new strategy to convert Bcr-Abl to be an apoptotic inducer by altering its subcellular localization. We show that a rapalog nuclear transport system (RNTS) containing six nuclear localization signals directs Bcr-Abl into the nucleus and that nuclear entrapped Bcr-Abl induces apoptosis and inhibits proliferation of CML cells by activating p73 and shutting down cytoplasmic oncogenic signals mediated by Bcr-Abl. Coupling cytoplasmic depletion with nuclear entrapment of Bcr-Abl synergistically enhances the inhibitory effect of nuclear Bcr-Abl on its oncogenicity in mice. These results provide evidence that direction of cytoplasmic Bcr-Abl to the nucleus offers an alternative CML therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / physiology*
  • Cell Growth Processes / physiology
  • Cell Nucleus / metabolism
  • Female
  • Fusion Proteins, bcr-abl / metabolism*
  • Humans
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / metabolism*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology*
  • Mice
  • Mice, Inbred C3H

Substances

  • Fusion Proteins, bcr-abl